Countries "approving" bitcoin just makes it actually legal to use and accept for merchants. correct me if I'm wrong
But not necessarily, some countries don't consider bitcoin as "legal" (or illegal). Yet, merchants are accepting it as a payment methods. In my opinion, the only benefit I can see from making bitcoin legal is earning peoples trust because people have this idea that bitcoin is used for bad things only (darknet) or that they will lose their money (mt.gox) etc. but after legalization, they'll know they are protected.
Well, true. Since bitcoin isn't "illegal"
(but not formally "legalized"), merchants can accept it as a payment method. But wouldn't the government sort of "pursue"(for a lack of a better word) the merchants that used BTC if ever BTC were to be banned someday in the future?